Unit 6: Biodiversity Environmental Science 1

Biodiversity 16 June 2010Biodiversity.ppt2 Variety of living things, number of kinds 3 Components of BD: 1. Ecological diversity –different habitats, niches, species interactions 2. Species diversity –different kinds of organisms, relationships among species 3. Genetic diversity –different genes & combinations of genes within populations

Benefits of Biodiversity Ecosystem functions Ecosystem services Cleaning water, Cleaning air, Habitat & breeding areas for wildlife, … Aesthetic and cultural benefits 16 June 2010Biodiversity.ppt3

Natural Resources Vital economic natural resources – Renewable Forests (plants, wildlife) Soils Fresh water (lakes, rivers) Wildlife and fisheries Rangeland – Nonrenewable Minerals Fossil Fuels 16 June 2010Biodiversity.ppt4

Natural Resources Management of natural resources – Assure availability of resources for the future – Three “philosophies” Maximum sustained yield Ecosystem-based management Adaptive management 16 June 2010Biodiversity.ppt5

Benefits of Biodiversity New food sources –Grains, fruits, vegetables, meat, fish 16 June 2010Biodiversity.ppt6

Benefits of Biodiversity Medicines Plants Jellyfish & sea anemones Nudibranchs Marine slugs 16 June 2010Biodiversity.ppt7

Biodiversity How much biodiversity 1.7—2.0 million species Estimates to 100 million 16 June 2010Biodiversity.ppt8

Biodiversity 16 June 2010Biodiversity.ppt9 Where is the biodiversity – Everywhere Every continent and habitat has unique life forms – Concentrated in the tropics Panama: > 500 species of breeding birds Arctic: species – Dense concentrations

Threats to Biodiversity Extinction and population reductions – Hunting and overharvesting Tiger Dodo Whales Sharks – Habitat loss 16 June 2010Biodiversity.ppt10

Threats to Biodiversity Extinction and population reductions – Pollution – Climate change – Invasive species 16 June 2010Biodiversity.ppt11

Protecting Biodiversity 16 June 2010Biodiversity.ppt12 How can we protect biodiversity – Stop overharvesting Sustainable yield Hunting & fishing laws (every state ?) – in developing nations ? – Protect habitat Refuges, parks, preserves – Endangered Species Act

Protecting Biodiversity Refuges, parks, preserves – How big should refuges be? – Where should they be? – McArthur & Wilson “Theory of Island Biogeography” colonization rate extinction rate (local) predicts number of species 16 June 2010Biodiversity.ppt13

Protecting Biodiversity 16 June 2010Biodiversity.ppt14 Island Biogeography – Island size predicts number of species

Protecting Biodiversity 16 June 2010Biodiversity.ppt15 Island Biogeography – Everyplace is an island – Habitat fragmentation Smaller fragments hold fewer species

Protecting Biodiversity Endangered Species Act (1973) – Goal to “recover” species so they no longer need protection under ESA – Implements U.S. participation in CITES “Convention on International Trade in Endangered Species” Prohibits trade in listed species – whole organisms – parts: skins, bones, teeth, flowers, leaves, etc. Other laws: – Marine Mammal Protection Act – Migratory Bird Treaty Act – Anadromous Fish Conservation Act – etc. 16 June 2010Biodiversity.ppt16

Protecting Biodiversity 16 June 2010Biodiversity.ppt17 Endangered Species Act (1973) – Listing of “endangered” and “threatened” species – Restricts development of habitats – Captive breeding programs Release of captive bred stocks to enhance or recover wild populations. endangered/ endangered/

Protecting Biodiversity 16 June 2010Biodiversity.ppt18 Biodiversity “hotspots” – Protection of habitat